gcvT

---
id: C5AUG2
gene_symbol: gcvT
product_type: PROTEIN
taxon:
  id: NCBITaxon:272630
  label: Methylorubrum extorquens AM1
description: 'gcvT encodes aminomethyltransferase (EC 2.1.2.10), also known as glycine
  cleavage system T protein, which catalyzes the final step of the glycine cleavage
  system: the transfer of the aminomethyl group from the lipoyl-bound intermediate
  (on gcvH) to tetrahydrofolate (THF), producing 5,10-methylene-THF and releasing
  ammonia. The enzyme belongs to the GcvT family and functions as a component of the
  glycine cleavage complex, working in concert with gcvP (P protein, glycine dehydrogenase),
  gcvH (H protein, lipoyl-carrier), and gcvL (L protein, dihydrolipoyl dehydrogenase).
  In methylotrophs, the glycine cleavage system connects the serine cycle to the THF
  one-carbon pool: glycine (produced from serine by serA) is oxidatively cleaved by
  the GCV system, generating 5,10-methylene-THF (which feeds into C1 metabolism),
  CO2, and ammonia. GcvT contains two characteristic domains: an aminomethyltransferase
  folate-binding domain (residues 25-274) and a C-terminal domain (residues 305-385).
  The enzyme is essential for glycine catabolism and for connecting amino acid metabolism
  to the THF-dependent one-carbon pool, allowing the organism to recycle one-carbon
  units between different pathways during methylotrophic growth.'
existing_annotations:
  - term:
      id: GO:0004047
      label: aminomethyltransferase activity
    evidence_type: IEA
    original_reference_id: GO_REF:0000120
    review:
      summary: This is the primary and specific catalytic activity of GcvT - the transfer
        of the aminomethyl group from the lipoyl-bound intermediate (on gcvH) to tetrahydrofolate,
        producing 5,10-methylene-THF and ammonia. [file:METEA/gcvT/gcvT-uniprot.txt,
        "aminomethyltransferase"; "N(6)-[(R)-S(8)-aminomethyldihydrolipoyl]-L-lysyl-[protein]
        + (6S)-5,6,7,8-tetrahydrofolate = N(6)-[(R)-dihydrolipoyl]-L-lysyl-[protein]
        + (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + NH4(+)"]
      action: ACCEPT
  - term:
      id: GO:0005960
      label: glycine cleavage complex
    evidence_type: IEA
    original_reference_id: GO_REF:0000002
    review:
      summary: GcvT is a component of the glycine cleavage complex, working together
        with gcvP, gcvH, and gcvL to catalyze the oxidative cleavage of glycine. This
        is the primary cellular location for the enzyme. [file:METEA/gcvT/gcvT-uniprot.txt,
        "Glycine cleavage system T protein"]
      action: ACCEPT
  - term:
      id: GO:0006546
      label: glycine catabolic process
    evidence_type: IEA
    original_reference_id: GO_REF:0000002
    review:
      summary: GcvT catalyzes the final step of glycine catabolism via the glycine
        cleavage system, transferring the aminomethyl group to THF and releasing ammonia.
        This connects glycine degradation to the one-carbon pool. [file:METEA/gcvT/gcvT-uniprot.txt,
        "Glycine cleavage system T protein"]
      action: ACCEPT
  - term:
      id: GO:0008483
      label: transaminase activity
    evidence_type: IEA
    original_reference_id: GO_REF:0000043
    review:
      summary: This is technically correct as GcvT transfers an aminomethyl group,
        but it's a somewhat misleading general term. The more specific term GO:0004047
        (aminomethyltransferase activity) provides better functional annotation.
      action: KEEP_AS_NON_CORE
  - term:
      id: GO:0016740
      label: transferase activity
    evidence_type: IEA
    original_reference_id: GO_REF:0000043
    review:
      summary: This is a very general parent term for all enzymes that transfer functional
        groups. While technically correct, the more specific term GO:0004047 provides
        much better functional annotation.
      action: KEEP_AS_NON_CORE
core_functions:
  - description: 'GcvT catalyzes the final step of the glycine cleavage system, transferring
      the aminomethyl group from the lipoyl-bound intermediate (on gcvH carrier protein)
      to tetrahydrofolate (THF), producing 5,10-methylene-THF and releasing ammonia.
      The enzyme functions as a component of the glycine cleavage complex, working
      in concert with gcvP (P protein), gcvH (H protein), and gcvL (L protein) to
      catalyze the oxidative cleavage of glycine. In the context of methylotrophic
      metabolism, the glycine cleavage system connects the serine cycle to the THF
      one-carbon pool: glycine (produced from serine) is oxidatively cleaved, generating
      5,10-methylene-THF that feeds into C1 metabolism, plus CO2 and ammonia. GcvT
      contains an aminomethyltransferase folate-binding domain and a C-terminal domain,
      and belongs to the GcvT family. The enzyme is essential for glycine catabolism
      and for recycling one-carbon units between amino acid metabolism and the THF-dependent
      one-carbon pool during methylotrophic growth.'
    molecular_function:
      id: GO:0004047
      label: aminomethyltransferase activity
    directly_involved_in:
      - id: GO:0006546
        label: glycine catabolic process
    supported_by:
      - reference_id: file:METEA/gcvT/gcvT-uniprot.txt
        supporting_text: aminomethyltransferase...Glycine cleavage system T protein...N(6)-[(R)-S(8)-aminomethyldihydrolipoyl]-L-lysyl-[protein]
          + (6S)-5,6,7,8-tetrahydrofolate = N(6)-[(R)-dihydrolipoyl]-L-lysyl-[protein]
          + (6R)-5,10-methylene-5,6,7,8-tetrahydrofolate + NH4(+)
    in_complex:
      id: GO:0005960
      label: glycine cleavage complex
references:
  - id: file:METEA/gcvT/gcvT-uniprot.txt
    title: UniProt entry for gcvT aminomethyltransferase
    findings: []
  - id: GO_REF:0000002
    title: Gene Ontology annotation through association of InterPro records with GO
      terms.
    findings: []
  - id: GO_REF:0000043
    title: Gene Ontology annotation based on UniProtKB/Swiss-Prot keyword mapping
    findings: []
  - id: GO_REF:0000120
    title: Combined Automated Annotation using Multiple IEA Methods.
    findings: []
status: COMPLETE